KGF 对 IEC-6的辐射防护作用与抑制 JNK／SAPK 的激活研究

摘要

Objective To observe the radioprotective effect of keratinocyte growth factor (KGF) by using the intestinal epithelial cell (IEC‐6) in vitro and to investigate the molecular mechanism of its action from the change JNK/SAPK cellular signal transduction pathway .Methods The in vitro cultured IEC‐6 was differentially treated by KGF and received the once radiation of the dose rate of 0 .589 Gy/min 60Coγray .The detections of cellular prolifera‐tion activity ,protein phosphokinase activity and JNK/SAPK protein phosphoric acid were performed .Results The KGF(10 ng/mL) pretreatment of IEC‐6 for 24 h could significantly reduce the cellular radiation sensitivity and in‐creased the radiation resistance;the KGF1 pretreatment inhibited the radiation‐induced JNK/SAPK (thr183/thr185) phosphorylation activation .Conclusion Suppressing the activation of JNK/SAPK molecule could be an important link of KGF radioprotective effect on intestinal epithelium .%目的：利用离体培养肠上皮细胞（IEC‐6）观察角质细胞生长因子（KGF）的辐射防护作用，并从c‐Jun氨基末端激酶（JNK）／应激活化蛋白激酶（SAPK）细胞信号传导途径的变化来探讨其作用的分子机制。方法离体培养IEC‐6分别经过KGF不同处理，接受剂量率为0．589 Gy／min ，60 Coγ射线一次性照射，进行细胞增殖活性、蛋白磷酸激酶活性和JNK／SAPK蛋白磷酸检测。结果 KGF （10 ng／mL）预处理IEC‐624 h可显著地降低细胞辐射敏感性，增高辐射抗性；KGFl预处理抑制辐射诱导 JNK／SAPK（thr183／thr185）磷酸化激活。结论抑制 JNK／SAPK分子的激活是KGF对小肠上皮辐射防护作用重要环节。